Integration of High Strength Steel (HSS) Elements in Automotive Industry

Abstract:

High Strength Steels (HSS) and Advanced High Strength Steels (AHSS) are most commonly used nowadays in the automotive industry to achieve a weight reduction of the vehicle while assuring that all the safety requirements are fulfilled. These steels are characterized by very high ultimate stresses, reaching up to 1500MPa with yield strengths of up to 1000MPa. It is mainly because of these exceptional mechanical properties that it is becoming very usual to find these steels in sheets. This study presents a design methodology for integrated security sub-modules (constituting the suspension and steering modules) in the car manufacturing industry. The sub-modules are made up of a steel structure and different anchorage elements (rubber-metal or plastic-metal), which undergo separate surface treatments to avoid corrosion. Afterwards, the elements are traditionally joined by means of adhesives and screws. This process involves a great number of stages, low quality union methods and generation of corrosion areas that shorten its service life. The first step in this study has been the construction of a metallic structure in high strength low alloy steel (HSLA), instead of in traditional steel, in order to benefit from its better safety performance and lower weight at affordable cost, moreover the industrial manufacturing process was simulate with F.E.M in order to reduce the cost in forming manufacturing process. The second step, the improvement proposed is based on the use of laser welding as joining method, a high quality way to reduce the number of anchorage points and to increase the resistance of the sub-module. The last step is the surface treatment on the integrated piece in order provide an unaltered coating. Overcoming the currently need of assembly processes, which usually causes serious damages on the protective surface, this treatment will suppose an increase in the response against corrosion of the pieces. Regarding this aspect, the development of an organic treatment with lower required temperatures (max. 100oC) has been proposed, paying particularly attention to the removal of pollutant elements (Cr (VI), Zn and Ni) involved in traditional methods. This methodology provides automotive suppliers an additional added value and cost reduction, allowing them to increase their competitiveness in a sector that faces up to the transition from the traditional supply chain to a strategic value chain.

• Periodical: Key Engineering Materials (Volume 549)
• Pages: 340-348
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.549.340
• Online since: April 2013
• Authors: Esteban Cañibano Álvarez, J.C. Merino Senovilla, J.Romo García, C. Maestro Martín, J. Sanz López
• Keywords: Finite Element (FE) Simulation, High Strength Steel (HSS), Safety Components

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